Anatomy of Microbursts
and the dangers they pose to aircraft
The anatomy of a microburst
shows that the highest wind speeds
occur shortly after the cold air has impinged upon the ground.
The spin-up of the microburst curl then results in an acceleration
of wind velocities about the curl.
An aircraft entering a microburst
will encounter strong headwinds, followed by
strong tailwinds, as it flies from one side of the microburst
to the other. If the pilot compensates for the headwind (to
decrease lift) a bit too much, then the aircraft will lose lift
in the tailwind and quickly strike the ground.
The end of microburst danger comes minutes after the air
reaches ground, but other microbursts will follow in many cases,
similar to repeated tornado events with a
cyclic supercell. It was
determined that one airliner crashed after it encountered
three microbursts in rapid succession upon final approach.
will occur with a plethora of thunderstorm types,
even dissipating anvil clouds in some cases. The important message is
that some thunderstorms or even weak convective showers which were
regarded as harmless a few years ago are now recognized to
be potential killers.
developing rain shaft